What TTL means
TTL is the maximum number of seconds a resolver may cache a DNS answer. Cached answers count down as time passes.
Network utility
DNS Lookup and TTL Inspector
Explore DNS record structure, recursive lookup steps, cache freshness, CNAME behavior, and TTL countdowns in a local educational resolver model.
- Runtime
- Browser
- Packets
- 0 real
- Mode
- Model
Lookup controls
The resolver uses local sample zones and generated documentation records.
45s
Resolver model ready.
Answer records
TTL values show remaining time after simulated cache age.
| Name | Type | TTL | Data |
|---|
Recursive trace
A simplified resolver path from cache to authoritative answer.
Recursive lookup
A recursive resolver may ask root, TLD, and authoritative servers, then cache the final response for future clients.
CNAME chains
A CNAME points one name at another canonical name. Resolvers continue the lookup until they find records for the requested type.
Usage guide
How to use the DNS TTL inspector
What this tool shows
It models DNS answers, CNAME follow-up, recursive lookup steps, and how cached TTL values decrease as simulated time passes.
How to test it
Try api.example.dev with A records, advance cache age, then switch record types to compare fresh answers, expired answers, and misses.
When it helps
Use it when teaching DNS caching, debugging propagation expectations, explaining CNAME chains, or showing why record changes are not instant everywhere.